#include "drv_adc.h"
uint32_t adc_buf[100]={0};
void drv_adc1_init(void)
{
	GPIO_InitTypeDef GPIO_InitStruct;
	ADC_CommonInitTypeDef ADC_CommonInitStruct;
	ADC_InitTypeDef ADC_InitStruct;
	DMA_InitTypeDef DMA_InitStruct;
	
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB | RCC_AHB1Periph_DMA2, ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
	
	GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AN;//模拟输入
	GPIO_InitStruct.GPIO_Pin = GPIO_Pin_1;
	GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;//浮空
	GPIO_Init(GPIOB, &GPIO_InitStruct);

	ADC_CommonInitStruct.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;//不使用DMA直接寄存器访问
	ADC_CommonInitStruct.ADC_Mode = ADC_Mode_Independent;
	ADC_CommonInitStruct.ADC_Prescaler = ADC_Prescaler_Div4;//84/4=21MHz,ADC的频率最高不超过36MHz
	ADC_CommonInitStruct.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;//采样周期5个时钟周期
	ADC_CommonInit(&ADC_CommonInitStruct);

	ADC_InitStruct.ADC_ContinuousConvMode = ENABLE;//使能连续转换
	ADC_InitStruct.ADC_DataAlign = ADC_DataAlign_Right;//数据右对齐
	ADC_InitStruct.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;//不使用外部触发
	ADC_InitStruct.ADC_NbrOfConversion = 1;//通道数
	ADC_InitStruct.ADC_Resolution = ADC_Resolution_12b;//12位分辨率
	ADC_InitStruct.ADC_ScanConvMode = DISABLE;//不扫描
	ADC_Init(ADC1, &ADC_InitStruct);
	
	DMA_InitStruct.DMA_BufferSize = 100;//需要搬运数据的数量
	DMA_InitStruct.DMA_Channel = DMA_Channel_0;//DMA通道，可任意选择
	DMA_InitStruct.DMA_DIR = DMA_DIR_PeripheralToMemory;//从外设到内存
	DMA_InitStruct.DMA_FIFOMode = DMA_FIFOMode_Disable;
	DMA_InitStruct.DMA_Memory0BaseAddr = (uint32_t)adc_buf;//目标地址
	DMA_InitStruct.DMA_MemoryBurst = DMA_MemoryBurst_Single;//单次突发
	DMA_InitStruct.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;//半字传输
	DMA_InitStruct.DMA_MemoryInc = DMA_MemoryInc_Enable;//地址自增
	DMA_InitStruct.DMA_Mode = DMA_Mode_Circular;//循环模式
	
	DMA_InitStruct.DMA_PeripheralBaseAddr = (uint32_t)&ADC1->DR;//数据源的地址
	DMA_InitStruct.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//单次突发
	DMA_InitStruct.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;//半字传输
	DMA_InitStruct.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设地址不自增
	DMA_InitStruct.DMA_Priority = DMA_Priority_High;//DMA的优先级
	DMA_Init(DMA2_Stream0, &DMA_InitStruct);

	ADC_RegularChannelConfig(ADC1, ADC_Channel_9, 1 , ADC_SampleTime_84Cycles);//设置采样规则和采样时间
	ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);//设置DMA触发条件
	ADC_DMACmd(ADC1, ENABLE);//使能ADC的DMA
	DMA_Cmd(DMA2_Stream0, ENABLE);//使能DMA
	ADC_Cmd(ADC1, ENABLE);
	ADC_SoftwareStartConv(ADC1);//触发ADC开始转换
	
}
uint16_t drv_adc_avg(void)
{
	uint8_t i=0;
	uint32_t sum=0;
	for(i=0;i<100;i++)
	{
		sum+=adc_buf[i];
	}
	return (uint16_t)(sum/100);
}

